The objective of the study is to select an optimal dose of taribavirin by comparing the efficacy and safety of 3 taribavirin dose levels, 20, 25, and 30 mg/kg/day, versus ribavirin 800 mg/day to 1400 mg/day based on subject body weight, with both drugs administered in combination with peginterferon alfa-2b to therapy-naive patients with chronic Hepatitis C Virus genotype 1 infection.